Masteries

Offense:
21

Defense:
9

Utility:
0

Introduction

Ok so I got Olaf and I've been playing around with a build for him.

The idea is to spam his E as much as possible because it hits so dang hard.
With cooldowns at 40% you can spam his E every 3 seconds.
The other nice thing is that his W (life steal and extra dmg) is a 7sec cool down with a 6 second duration. This lets him constantly have his dmg. Mana health and cooldowns are then my primary concerns.

My Runes:
9x Greater Mark of Strength
9x Greater Seal of Stregth
9x Greater Glyph of Focus
3x Greater Quintessence of Desolation but you can also go with Alacrity

I use this skill order because Early - Mid game Recklesss Swing hurts so bad. I also take reckless swing 2nd because I play aggressively in the lane and it can often help me with firstlblood.
Summon Spells:

I use ignite & exhaust. I build to kill though. I find exhaust vs another physical dmger lets me build my hp back up with vicious strikes.
With such spameable skills you will make great use of the locket.

Its my opinion that if you build olaf this way he is very powerful mid game. Reckelss swing does true damage and nothing increases its damage except cool down reduction. Obviously a skill like this means that if you max it at lvl 9 instead of later in the match its maximally effective. It will do less and less dmg as people gear up and lvl.

For this reason I think its important to be dominating the mid game with a maxed reckless swing. If you use W first you barely take any dmg from the swing. With innervating locket you gain it right back. Its a great way to carry yourself into an end game build.Neither undertow nor reckless swings is cancelled by pantheon's passive block. I don't think jax can dodge them either. Mord's shield is not bypassed.

Runes

My Runes:
9x Greater Mark of Strength
9x Greater Seal of Stregth
9x Greater Glyph of Focus
3x Greater Quintessence of Desolation but you can also go with Alacrity

Items

Ruby Crystal makes up some good health early and also, brings you closer to warmogs.

Regrowth Pendant gives the regen. to stay a long time in lane and it brings you one step closer to warmogs.

Warmog's Armor is one of my favorites item's to Olaf, because of the health and Olaf's passive.

Atma's Impaler is simple great to this build, it gives some good dmg(because of the Warmog's Armor and then combined with the passive) and some armor this is a must i thing because when you get the frozen mallet as the next item Atma's will give you some heavy dmg.

Frozen Mallet well lets just say it gives you the lat needed health and its passive is helping you out. when you get this well lets just say the game should not be a problem anymore.

The Bloodthister it gives you 60 dmg and when it is stacked 100 dmg with this dmg and its passive life steal you would now be able to kill 2 or 3 in team battles.

Abilities

UNDERTOW - Olaf throws an axe into the ground at a target location, dealing damage to units it passes through and slowing their movement speed. If Olaf picks up the axe, the ability's cooldown is reduced by 6 seconds. Olaf throws an axe to a target location, dealing 50/90/130/170/210 (+) physical damage to units it passes through and slowing them by 24/28/32/36/40% for 2.5 seconds. If Olaf picks up the axe, the ability's cooldown is reduced by 6 seconds. Pretty sweet move, use it sparingly even though it has a low mana cost.
Cost55/60/65/70/75 ManaRange1000

VICIOUS STRIKES - Olaf's attack damage is increased, based on his health, and he gains massive lifesteal and spell vamp. For 6 seconds, Olaf's attack damage is increased by 7/14/21/28/35 (+ [1% of maximum Health]) and he gains 9/12/15/18/21% lifesteal and spell vamp.
Cost40/45/50/55/60 ManaRange700

RECKLESS SWING - Olaf attacks with such force that it deals true damage to his target and himself. Olaf deals 100/160/220/280/340 true damage to his target and inflicts 40/64/88/112/136 true damage to himself.
Cost50/50/50/50/50 ManaRange325

I use this skill order because Early - Mid game Recklesss Swing hurts so bad. I also take reckless swing 2nd because I play aggressively in the lane and it can often help me with firstlblood.

Summoner Spells

I use ignite & exhaust. I build to kill though. I find exhaust vs another physical dmger lets me build my hp back up with vicious strikes.

But you can also use flash and exhaust..

flash is better than ghost because olaf doesnt need ghost he got ult that makes him able to escape almost every time. flash is also a good way to make some distance to the enemy.
otherwise it is also good to assault but i recommend to use it if enemy is trying to flee.

well exhaust is always good you can make the enemy unable to dmg you and it slows like hell! its a must i think.
++ Since the new masteries you can upgrade your exhaust & ignite and make it even more powerful.

Gameplay

As Olaf you always need to be fearless, don't run from something you can't escape (unless you have you ult). You often are far better off fighting things out or just not getting into those nasty situations in the first place. Olaf is one of the best 1v1 champions, that is because of his passive which makes you need to be a little reckless sometimes. But remember sometimes you can't be too reckless, like around a caster.

Using abilities:

Undertow: Throw this thing only as far as it needs to go, don't throw it full length 100% of the time because then you will have to go farther to get it. if you spam it to much you will have huge mana problems.

Vicious Stirkes: Use this ability against squishies when you do not have full health. This will give you much more health and will rip them up. If you have to use it against a tank.

Reckless Swing: A great move, it goes right trough resistences so it is a great way to start and finish a battle. You need to be careful, don't use this if your running away from somebody.

Ragnarok: This is beast! You become immune to disables, go faster and gain resistences. This is the perfect gettaway out of almost anything.

Team Work

What your job is in a teamfight is fairly straightforward. Talk to your team and agree which champion on the opposing team is most dangerous (whether it is their AP carry or physical carry). Then wait for the teamfight to start, turn on your ult (BEFORE YOU GET FOCUSED DOWN--THIS IS IMPORTANT). You want to use your ult pretty much as soon as the teamfight starts even if you aren't getting focused. So you pop your ult and immediately take our their carry. There is no way to slow or disable you and you should be able to take out their carry before their team even gets you to half health. Remember to use Vicious Strikes as soon as you get in melee range, and reckless swing on the person you are focusing. You'll find if you are doing fairly well in the game and have your ult up you can 2v1 almost any 2 characters in the game (if they aren't fed), using your ult and your natural life steal (take down the squishy person first).

Creeping / Jungling

Olaf is a good jungler.
His ganks are very good (Unlike what most will tell you)
His speed is very good.
He's a very good jungler..
But, there's simply not enough gold and levels in the jungler for a gold and level reliant champion like Olaf.
If you jungle Olaf, you'll feel weak mid game.
If you solo lane him, you will feel strong all game.

++ Olaf is pretty much all based on the mid game levels so.. I don't recommend jungling if you want to play your best game and get unstoppable..

Farming

To farm is really important early game. try always hit the minions 1 or 2 times then wait to its low on health because your own minions are attacking them. then make the last hit to always get some easy gold.(while waiting on the minion to get low begin on another minon so you fast get 2 minion kills)

Summary

With such spameable skills you will make great use of the locket.

Its my opinion that if you build olaf this way he is very powerful mid game. Reckelss swing does true damage and nothing increases its damage except cool down reduction. Obviously a skill like this means that if you max it at lvl 9 instead of later in the match its maximally effective. It will do less and less dmg as people gear up and lvl.

For this reason I think its important to be dominating the mid game with a maxed reckless swing. If you use W first you barely take any dmg from the swing. With innervating locket you gain it right back. Its a great way to carry yourself into an end game build.